SNOAAA7 April   2024 LMG3522R030

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Overview of Inverter Model
    1. 2.1 Power Stage
    2. 2.2 Control and Modulation Method
  6. 3Realization of Digital Control Using C-Script Block
    1. 3.1 Overview of Project Structure
    2. 3.2 AC Voltage Sampling and True RMS Value Calculation
    3. 3.3 Multiple Loop Control
      1. 3.3.1 Voltage Loop With Notch Filter
      2. 3.3.2 Current Loop With PI Compensator Anti-Windup
      3. 3.3.3 Sinusoidal and Sawtooth Wave Generator
      4. 3.3.4 Totem-Pole Modulation and Dead-Time Control
  7. 4Simulation Results
  8. 5Summary
  9. 6References

2.1 Power Stage

Figure 2-1 shows an overview of the inverter model, where the C-Script represents the digital controller that is used to sample data, calculate control parameters, and output the PWM signal. Power stage parameter is the same as the PMP23338 reference design, and the specifications are listed in Table 2-1. Conventional H-bridge topology with LC output filter is used. TI GaN devices LMG352xR030 are used in the high-frequency bridge and common Si FETs are used as the low-frequency bridge (50/60Hz).

Table 2-1 Power Stage Specifications
Parameter Specifications Units
Input Voltage 380 V
Output Voltage 220 VRMS
Output Voltage Frequency 50 Hz
Output Power 3.6 kW
Output Current 16 ARMS
PWM Frequency (GaN Bridge) 100 kHz
PWM Frequency (SI Bridge) 50 Hz
GUID-20240319-SS0I-HJFW-LBPR-FXGM2QTLXQPV-low.svg Figure 2-1 Inverter Model Overview

This model also provides an interface to the switch modulation method, simply change to unipolar modulation by copying the output PWM signal into the unipolar modulation block.